1. Field of the Invention
The present invention relates to an optical connector adapter with a shutter, which connects an optical fiber attached to an optical connector plug (hereinafter simply referred to as a first optical connector plug) with an optical fiber attached to the other optical connector plug (hereinafter simply referred to as a second optical connector plug). The present invention also relates to an optical connector assembly in which an optical connector plug is fitted into the optical connector adapter with a shutter.
2. Discussion of the Background
In typical optical communications, an optical connector is generally utilized to connect multiple optical fibers with each other. The optical connector is composed of a first optical connector plug that holds a tip of an optical fiber, a second optical connector plug that also holds a tip of another optical fiber, and a cylindrical optical connector adapter into which both the first and second optical connector plugs are inserted while facing each other. Since both the first and second optical connector plugs are inserted into the optical connector adapter while facing each other, the optical fiber of the first optical connector plug and that of the second optical connector plug are optically connected to each other.
As described with reference to FIGS. 8, 9, and 10 in a first patent literature (Japanese Patent Application Registration No. 5,138,005 (JP-5,138,005-B)), in a body of an known optical connector adapter that accommodates a shutter, a receiving hole is formed to penetrate the body of the optical connector adapter and accept insertion and removal of a first optical connector plug at one side thereof and insertion and removal of a second optical connector plug at the other side thereof as well. In the receiving hole of the known optical connector adapter with the shutter, an inclined shutter plate is installed extending in a prescribed direction therein. When the first optical connector plug is inserted into the receiving hole from one side of the optical connector adapter with the shutter, since light having optical high power outputted from a tip of the optical fiber of the first optical connector plug is blocked by the shutter plate, eyes of an operator are protected. When a second optical connector plug is inserted into the receiving hole from the other side thereof, the optical fiber of the first optical connector plug and that of the second optical connector plug are optically connected to each other after the shutter plate is pushed down by the second optical connector plug.
As also described with reference to FIG. 2 in a second patent literature (Japanese Patent Application Publication No. 2013-235229 (JP-2013-235229-A)), another known optical connector adapter includes outer and inner cylindrical housings. That is, the outer and inner cylindrical housings are each divided into two pieces at a center in a longitudinal direction thereof, respectively. One of segments of the inner cylindrical housing is inserted into one of segments of the outer cylindrical housing, while the other one of segments of the inner cylindrical housing is inserted into the other one of segments of the outer cylindrical housing again. The segments of the outer cylindrical housing are then connected to each other. In one of the segments of the inner cylindrical housing of this known optical connector adapter, a pair of first latches is disposed at a prescribed interval in its widthwise direction to engage with and disengage from side portions of a first optical connector plug, respectively. The pair of first latches is connected via upper and bottom wall portions of the inner cylindrical housing. Similarly, in the other one of segments of the inner cylindrical housing of this known optical connector adapter, a pair of second latches is also formed at a prescribed interval in its widthwise direction to engage with and disengage from side portions of a second optical connector plug, respectively. The pair of second latches is connected via upper and bottom wall portions again.
As also described with reference to FIGS. 4 and 5 in a third patent literature (Chinese Patent Application Publication No. 102,645,710 (CN-102,645,710-A)), yet another known optical connector adapter includes a cylindrical inner housing inserted into an outer cylindrical housing in a prescribed direction to be secured thereto. In one of opening sections of the inner cylindrical housing of this known optical connector adapter, a pair of first latches is formed at a prescribed interval in its widthwise direction to engage with and disengage from side portions of a first optical connector plug, respectively. In the other one of opening sections of the inner cylindrical housing of this known optical connector adapter, a pair of second latches is formed again at a prescribed interval in its widthwise direction to engage with and disengage from side portions of a second optical connector plug, respectively. The pairs of first and second latches are each connected via upper and bottom wall portions again. The inner cylindrical housing includes a fixed latch formed at its center to engage with the outer cylindrical housing to be secured thereto.
According to the known optical connector adapter the with shutter of the first patent literature (JP-5,138,005-B), light having optical high power outputted from the tip of the optical fiber hits the shutter plate and is thereby blocked as shown in FIGS. 8 to 10 of the first patent literature (JP-5,138,005-B). However, due to hitting the shutter plate, the light having optical high power is reflected by the shutter plate and illuminates a side wall of a plug insertion through hole. Since the light having optical high power outputted to the side wall of the plug insertion through hole turns into (i.e., generates) heat, an adapter body with the plug insertion through hole is accordingly heated consequently. Hence, when the known optical connector adapter is used over relatively the long time, the adapter body generally causes thermal degradation and/or thermal deformation or the like, thereby possibly raising a problem. At the same time, an optical connector plug also similarly causes thermal degradation and/or thermal deformation as well due to generated heat, thereby possibly raising a problem again.
In particular, since power of light having optical high power transmitted from an optical fiber tends to increase in recent years, an optical system capable of emitting high power laser having optical power greater than 0.1 W has been introduced. In the future, an optical communications system that emits optical power greater than 0.5 W is supposed to come into practical use. In addition, an optical connector that holds an optical fiber ribbon (e.g., a four-core wire, an eight-core wire, and a twelve-core wire) obtained by juxtaposing multiple optical fibers is increasingly spreading recently. For this reason, light beams having optical high power outputted from tips of these optical fibers and reflected by the shutter plate irradiate the side wall of the plug insertion through hole, thereby likely heating up the adapter body. When it is heated up, the adapter body generates thermal deformation thereby possibly disturbing insertion and removal of the first and second optical connector plugs. At the same time, material that constitutes the optical connector adapter with the shutter may output volatile substance that pollutes the first and second optical connector plugs. Furthermore, since it is heated, the optical connector plug may cause heat deformation again.
Recently, a prescribed optical connector adapter with the shutter circulates on the market, which attempts to prevent an adapter body from the thermal deformation and thermal degradation by employing metal in producing the adaptor body. In such an optical connector adapter with the shutter, however, since temperature of the adapter body rises as a whole, an operator is possibly thermally injured when he or she touches an end face of the optical connector adapter with the shutter.
In the optical connector adapter of the second patent literature (JP-2013-235229-A), since the pair of first latches separated at a prescribed interval in the widthwise direction of the inner cylindrical housing is connected to each other via the upper and bottom walls, and one of segments of the inner cylindrical housing has a cylindrical shape as shown in FIG. 2 of the second patent literature (JP-2013-235229-A), while the pair of second latches is similarly connected to each other via the upper and bottom walls, and the other one of segments of the inner cylindrical housing has a cylindrical shape again, when a through section is formed to penetrate the optical connector adapter from the receiving hole, into and from which the first optical connector plug is inserted and removed, to an outside of the optical connector adapter, multiple through sections are needed in both parts (i.e., one of the segments of the outer cylindrical housing and one of the segments of the inner cylindrical housing), respectively. Further, since upper and bottom walls of one of the segments of the inner cylindrical housing needs to be left unoccupied, a position and a size of an available through section are limited.
Similarly, as described with reference to FIGS. 3, 4, and 5 in the third patent literature (CN-102,645,710-A), in the optical connector adapter, since the pair of first latches separated at a prescribed interval in the widthwise direction of the inner cylindrical housing is connected to each other via the upper and bottom walls thereof again, while the pair of second latches is also connected to each other via the upper and bottom walls of the inner cylindrical housing as well so that the inner cylindrical housing has a cylindrical shape again, when a through section is formed to penetrate the optical connector adapter from the receiving hole, into and from which the first optical connector plug is inserted and removed, to an outside of the optical connector adapter, multiple through sections are also needed in both parts (i.e., the outer cylindrical housing and the inner cylindrical housing), respectively. Further, since upper and under walls of one of the segments of the inner cylindrical housing needs to be left unoccupied, a position and a size of an available through section are limited again.
In this respect, a developed optical connector adapter with a shutter capable of blocking light having optical high power outputted from an optical fiber and thereby suppressing a rise in temperature of an adapter body by using a countermeasure against the light having optical high power can be provided. Also provided is a development optical connector adapter with a shutter capable of employing a through section that penetrates the optical connector adapter from a receiving hole to an outside of the optical connector adapter regardless of location and size thereof.
Herein below, optical power greater than 0.1 W is simply referred to as high power. When an optical fiber ribbon is used and the sum of optical power outputted from multiple optical fibers thereof is 0.1 W or more, it is also simply referred to as the high power.